1. Field of the Invention
The invention relates to an architectural covering having a plurality of adjustable and retractable slats. In particular to an architectural covering that further includes a fixed stationary rail at one end of its plurality of slats, a movable rail at an opposite end of the plurality of slats, which is movable to and from the fixed rail to create extended and retracted positions of the architectural covering. In the operation of such blinds, in one form, raising and lowering of the movable rail is controlled by at least one continuous cord that is arranged in a closed loop with both its opposite ends attached to the movable rail.
2. Description of the Relevant Art
Such a retractable slatted covering is known from U.S. Pat. No. 4,687,041. In this window covering at least one fixed cord return guide is adapted to be stationary mounted in a plane extending through the fixed rail, the plurality of slats and the movable rail. The fixed cord return guide is positioned at a location spaced from the fixed rail and beyond the movable rail to an extent determined by a maximum extension required for the covering. In combination with pleated blinds it has been proposed to drive the movable rail by driving the looped continuous cord, as disclosed in U.S. Pat. No. 6,119,755. While usually the raising and lowering mechanisms of pleated blinds can be readily adapted to slatted venetian blinds, an inconvenience presents itself when it is attempted to use the raising and lowering drive also for tilting the slats. In such, so-called, mono-commando versions premature raising can occur while the slats are being tilted.